• Membrane Journal
• /
• v.8 no.3
• /
• pp.138-147
• /
• 1998

This paper compared selectivities and mass transfer rates of valuable aromatics (naphthalene group: carbon number 10-12) in the light cycle oil obtained from solvent extraction (SE) with those obtained from liquid membrane permeation (LMP). An aqueous solution of dimethylsulfoxide (DMSO) and an aqueous solution of saporrin and DMSO were used as extraction solvent of SE and the membrane phase of LMP, respectivdy. Selectivities of naphthalene group in reference to n-nonane obtained from SE runs were rapidly increased with decreasing the operating temperature, whereas, those obtained from LMP runs were remained constant throughout the operating temperature. At room temperature, selectivities of naphthalene group obtained from SE were greater than those from SE. Furthermore, mass transfer rates of naphthalene group by SE and LMP were measured in a baffled batch stirred vessel. It was found that the extraction rates of SE were faster by about 280 times than the permeation rates of LMP.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2001.10a
• /
• pp.258-263
• /
• 2001

In this paper, the real-time prediction of high temperature creep life was carried out for the friction welded joints of dissimilar heat resistintg steels (CulCr0.5Zr-STS316L). Various life prediction methods such as LMP (Larson-Miller Parameter) and ISM (initial strain method) were applied. The creep behaviors of those steels and the welds under static load were examined by ISM combined with LMP at 300, 400 and 50$0^{\circ}C$, and the relationship between these two methods was investigated. A real-time creep life (tsub/r/, hr) prediction equation by initial strain ($\varepsilon_0$, %) under any creep stress ($\sigma$, MP$\alpha$) at any high temperature (T, K) was developed

• Journal of Mechanical Science and Technology
• /
• v.17 no.4
• /
• pp.469-476
• /
• 2003

Despite of considerable research results or uniaxial tension creep available for superalloys, few studies have been made on high temperature creep using the Initial Stram Method (ISM) In this paper, the real-time prediction of high temperature creep strength and creep lift for the nickel-based superalloy Udimet 720 (high-temperature and high-pressure gas turbine engine materials) was performed on round-bar type specimens under pure static load at the temperatures of 538$^{\circ}C$. 649$^{\circ}C$, and 704$^{\circ}C$. The predictive equation derived from the ISM in creep tests showed better reliability than those from LMP (Larson-Miller Parameter) and LMP-lSM (Larson Miller Parameter-Initial Strain Method) specially for long time creep prediction (10$^3$∼10$\^$5/h).

• Proceedings of the KIEE Conference
• /
• 2006.07a
• /
• pp.365-367
• /
• 2006

송전망은 전력수송을 가능하게 함으로써, 경쟁적 전력시장을 지지하는 하부구조의 역할을 한다. 하지만 송전망은 여러 제약조건에 의해 수송 한계에 다다를 수 있고 이렇게 공급능력의 한계를 벗어남으로써 발생한 송전혼잡은 전체 계통운영에 있어서 비용 상승을 일으킨다. 본고에서는 송전선로 내 혼잡이 가격에 미치는 영향을 알고 그로 인한 각 모선의 LMP(Locational Marginal Price) 형성에 대해 세부적으로 연구하였다. 그리고 입찰방법을 단순히 이상적인 상창이 아닌 송전 혼잡으로 인해 전력 공급자가 시장지배력을 갖게 되었을 경우에 대하여 적절한 입찰전략의 필요성을 언급하고 가능한 방법을 생각해 보았다.

• Proceedings of the KIEE Conference
• /
• 2004.11b
• /
• pp.97-100
• /
• 2004

As the circumstance of the traditional system is changed according to power system deregulation, the simulation tool which should reflect market code providing market operating mechanism is needed to analyze an electricity market. This paper presents the development of Electricity Market Price Simulator for short term(EMPS) that is designed to imitate the Korean electricity market. The EMPS is developed in VB.NET and is composed if three functions that consist of calculating SMP for CBP market, MCP for TWBF market and LMP for LMP-market. To evidence the features and the performance of EMPS, a small two way bidding market with 12-bus system, one way bidding market for generator competition and LMP market with 5-bus system will be presented for the electricity market simulations using EMPS.

• Journal of Life Science
• /
• v.25 no.3
• /
• pp.269-275
• /
• 2015

Collagen peptides, which are found at high concentrations in the human body, are present in animal bones and the skin of marine organisms, namely, fish scales. Collagen is the most abundant structural protein of various connective tissues in animals. Furthermore, it is widely used in biomedical material, pharmaceutical, cosmetic, food, and leather industries. Peptides extracted from scales of various fish protect against ultraviolet B (UVB)-induced skin damage and photo-aging. However, the protective effects of collagen peptides derived from the scales of Branchiostegus japonicus against UVB exposure are unclear. This study investigated the effects of peptides larger than 1 kDa (high-molecular weight peptides [HMP]) and smaller than 1 kDa (low-molecular weight peptides [LMP]), derived from extracts of B. japonicus scales, against UVB-induced skin damage and photo-aging. These peptides scavenged 1,1-diphenyl-2-picrylhydrazyl radicals in a dose-dependent manner. In UVB-exposed HaCaT human keratinocytes, LMP inhibited 8-isoprostane generation, a marker of cellular lipid peroxidation. The peptides also suppressed the UVB-induced increase in tyrosinase activity and melanin content in B16F10 mouse melanoma cells. In addition, the LMP and HMP treatment suppressed UVB-induced elastase and matrix metalloproteinase-1 activities in the HaCaT cells. These results indicate that peptides derived from B. japonicus scales have antioxidant, antiphoto-aging, and skin-whitening effects.

• IMMUNE NETWORK
• /
• v.23 no.2
• /
• pp.17.1-17.16
• /
• 2023

Latent membrane protein 2A (LMP2A), a latent Ag commonly expressed in Epstein-Barr virus (EBV)-infected host cells, is a target for adoptive T cell therapy in EBV-associated malignancies. To define whether individual human leukocyte antigen (HLA) allotypes are used preferentially in EBV-specific T lymphocyte responses, LMP2A-specific CD8⁺ and CD4⁺ T cell responses in 50 healthy donors were analyzed by ELISPOT assay using artificial Ag-presenting cells expressing a single allotype. CD8⁺ T cell responses were significantly higher than CD4⁺ T cell responses. CD8⁺ T cell responses were ranked from highest to lowest in the order HLA-A, HLA-B, and HLA-C loci, and CD4⁺ T cell responses were ranked in the order HLA-DR, HLA-DP, and HLA-DQ loci. Among the 32 HLA class I and 56 HLA class II allotypes, 6 HLA-A, 7 HLA-B, 5 HLA-C, 10 HLA-DR, 2 HLA-DQ, and 2 HLA-DP allotypes showed T cell responses higher than 50 spot-forming cells (SFCs)/5×105 CD8⁺ or CD4⁺ T cells. Twenty-nine donors (58%) showed a high T cell response to at least one allotype of HLA class I or class II, and 4 donors (8%) had a high response to both HLA class I and class II allotypes. Interestingly, we observed an inverse correlation between the proportion of LMP2A-specific T cell responses and the frequency of HLA class I and II allotypes. These data demonstrate the allele dominance of LMP2A-specific T cell responses among HLA allotypes and their intra-individual dominance in response to only a few allotypes in an individual, which may provide useful information for genetic, pathogenic, and immunotherapeutic approaches to EBV-associated diseases.

• Journal of Ocean Engineering and Technology
• /
• v.15 no.3
• /
• pp.43-48
• /
• 2001

In this paper, the real-time prediction of high temperature creep strength and creep for nickel-based superalloy Udimet 720 (high-temperature and high-pressure gas turbine engine materials) was performed on round-bar type specimens under pure load at the temperatures of 538, 649 and 704$^{\circ}C$. The predictive equation of ISM creep has better reliability than that of LMP and LMP-ISM, and its reliability is getting better for long time creep prediction ($10^3~10^5$h).

• The Korean Journal of Cytopathology
• /
• v.12 no.2
• /
• pp.73-80
• /
• 2001

The prevalence of Epstein-Barr virus(EBV) in the uterine cervix was investigated to define the possible etiologic role in cervical carcinogenesis. The viral genotyping and LMP-1 30bp deletion were also stooled. The materials included 169 uterine cervical swabs(152 within normal limits, 12 atypical squamous cells of uncertain significance, 3 low grade intraepithelial lesions, and 2 high grade squamous intraepithelial lesion) and 104 uterine cervical tissues obtained from hysterectomy specimens(32 carcinoma in situ, 9 microinvasive squamous cell carcinomas, 37 invasive squamous cell carcinomas, 7 adenocarcinomas, 7 adenosquamous carcinomas, and 12 cervicitis). EBV detected by PCR for EBNA-1 was positive in 52(56.5%) of 92 invasive and noninvasive cervical carcinomas, and 80(48.8%) of 164 inflammatory or normal cervices. The viruses detected in carcinomas were all type A, and LMP-1 30bp deletion form was more frequent in premalignant and malignant cervical lesions than in nonneoplastic cervices. From the above results, it may be concluded that EBV is one of common viruses detected in uterine cervix of Korean women, and type A virus and LMP-1 30bp deletion form may have a role in cervical carcinogenesis.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.27 no.1
• /
• pp.15-26
• /
• 2023

The purpose of this study is to determine the artificial intelligence-based degradation index from the image of the cross-section of the microstructure taken with a scanning electron microscope of the specimen obtained by the creep test of DA-5161 SX, a nickel-based superalloy used as a material for high-temperature parts. It proposes a new method of quantification and proposes a model that predicts degradation based on Bayesian inference without destroying components of high-temperature parts of operating equipment and a creep life prediction model that predicts Larson-Miller Parameter (LMP). It is proposed that the new degradation indexing method that infers a consistent representative value from a small amount of images based on the geometrical characteristics of the gamma prime phase, a nickel-base superalloy microstructure, and the prediction method of degradation index and LMP with information on the environmental conditions of the material without destroying high-temperature parts.